摘要
盐胁迫明显抑制杨树幼苗高生长,其高生长速率随胁迫时间的延长和盐浓度的增加而减小,与此同时,叶片中Cl ̄-、Na ̄+的累积则增加,叶片中游离脯氨酸的累积在胁迫后约2~3d达到峰值,K ̄+累积则在胁迫后约2周迅速增加,两者都是在峰值之后随胁迫时间的延长而下降。杨树幼苗对Ci ̄-和Na ̄+的吸收并不同步,胁迫后期Na ̄+/Cl ̄-的值逐渐升高,在浓度为0.3%的处理组比值可达1.5.同时,Na ̄+/K ̄+值的升高是Na ̄+吸收增加而K ̄+吸收减少的结果。外源K ̄+、Ca ̄2+对盐胁迫抑制高生长有一定的缓解作用,但K+的作用不及Ca2+。
Salt-stress inhibits the height growth of poplar seedlings significantly, and the rate of height growth decreases with the lasting of salt-stress and increase in salinity from 0. 1 % to 0. 3%. Meanwhile, the accumulation of Cl ̄- and Na ̄+ in leaves increases. Free proline accumulation in leaves culminates after 2~ 3 days of salt stress, K ̄+ accumulation increases rapidly after about 2 weeks of Salt stress, both of which decrease after the culmination with the extension of salt stress. The absorption by poplar seedlings of Cl ̄- and Na ̄+ doesn't take place simultaneously. In later sarge of salt stress the value of Na ̄+ /Cl ̄- rises gradually. Under 0. 3% level of salinity, this value may reach 1. 5, and the rise of Na ̄+/K ̄+ value results from the increase of Na ̄+ absorption and the decrease of K ̄+. External K ̄+ and Ca ̄2+ can reduce the inhibition of salt stress to height growth to a certain degree, but the effect of K ̄+ is not as good as that of Ca ̄2+.
出处
《南京林业大学学报(自然科学版)》
CAS
CSCD
1994年第4期13-18,共6页
Journal of Nanjing Forestry University:Natural Sciences Edition
基金
国家自然科学基金
关键词
杨树
新无性系
盐胁迫
游离脯氨酸
生长速率
New poplar clones, Salt stress, Free proline, Relative height growth rate